What is pertaining to, or resembling, a cycloid; as, the cycloidal space is the space contained between a cycloid and its base. Cycloidal engine. See Geometric lathe called?

cycloidal — Pertaining to, or resembling, a cycloid; as, the cycloidal space is the space contained between a cycloid and its base. Cycloidal engine. See Geometric lathe. (Webster's 1913.)

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